The antidote effect of thiosulphate and hydroxocobalamin in formation of nitroprusside intoxication of rabbits

Abstract

Sodium nitroprusside (SNP) and hydroxocobalamin (HC) - in molar ratios of 1:4, 1:5, and 1:8, respectively - were infused simultaneously during 4 h into two veins of separate ears of conscious rabbits. Controls received HC only. Sodium thiosulphate (ST) was infused with SNP at molar ratios of 1:4, 1:5, and 1:10. The observation period was 48 h. With the lowest dose of HC (1:4), SNP produced a severe metabolic acidosis; three of ten animals died during the infusion, an additional six within 24 h. When the 1:5 ratio was administered, the acidosis was less marked, but still three of seven animals succumbed within 24 h. The highest dose (1:8) prevented acidosis, however three of eight animals died. All doses of HC caused histological changes in the liver, the myocardium, and the kidney, independently if given alone or with SNP. In contrast to this, ST had a complete antidote effect, if administered in a 1:5 ratio; no acidosis was demonstrable and death did not occur. In neither dosage ST could prevent histological changes in the liver, but the kidney and the heart were not affected. In contrast to HC ST alone did not cause histological alterations. Consequently, ST is the preferable antidote and is superior to HC for preventing or treating intoxications with SNP.

An autism cohort study of cobalt levels following vitamin B12 injections

“…Following vitamin B12 (hydroxocobalamin) intraperitoneal administration (70 mg kg À1 day À1 ) for a 21-day period to rats, investigators observed significant increases in the examined tissue concentrations of cobalt in the diaphragm and myocardium (other organs were not examined) (Pery-Man et al 1996), and no significant adverse histological effects of vitamin B12 administration was observed in the tissues examined. In contrast, investigators observed that intravenous administration of a single several-hundred milligramper-kilogram dose of vitamin B12 (hydroxocobalamin) to rabbits produced significant acute histological changes to organs, including the kidney, liver, and heart (Hobel et al 1980). Importantly, since neither of these two studies attempted to study the potential adverse histological effects of chronic long-term low doses of vitamin B12 in organs such as the brain, one cannot make any concrete extrapolation from the results reported in these animal studies to the injection of methylcobalamin into humans.…”

Nitroprusside and metal nitroprusside nano analogues for cancer therapy

“…In addition, these substances also interfere with iodine uptake by disrupting metabolism of thyroid and vitamin B12 [49]. In this context, Hobel et al evaluated the antidote effect of hydroxocobalamin and thio-sulphate after infusing sodium nitroprusside into the rabbits [50].…”